<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <p>
        <hr color="red">
        <hr color="blue">
        <hr color="pink">
        <hr color="green" width="300px" align="left">
        <hr noshade><!-- 去掉阴影 -->
    </p>
</body>

</html>